Pump control device



Aug. 20, 1929. c. A. SCHELLENS PUMP CONTROL DEVICE Filed June 26, 1925 2 Sheets-Sheet 4% ATTORNEYS Aug. 20, 1929. c. A. SCHELLENS 1,725,722

PUMP CONTROL DEVICE Filed June 26, 1925 2 Sheets-Sheet 2 Patented Aug. 20, 1929.

UNITED STATES rarer QFFEQE.

cn'nrsrornna A. SCHELLENS, or MARBLEHEAD, I/IASSACHUSETTS, Assrenon, BY

Mnsnn ASSIGNMENTS, 'ro c-s nnernnnarne COMPANY, A ooaroaerron or DEL- AVIARE.

BUMP CONTROL DEVICE.

Application filed June 26, 1925. Serial No. 39,579.

This invent-ion relates to pump control devices and is particularly useful in connection with rotary or centrifugal pumps and I have illustrated and described my invention as applied to the feed-water system of a locomotive for which the invention is especially adaptable.

Qne of the primary difficulties encountered in connection with pumps, particularly ro- 1o tary pumps, is the prevention of over-speeding. In this connection it has been heretofore contemplated to provide mechanically operated means for closing the pump steam supply when the pump approaches a dangerous speed, but this method of control is disadvantageous in that, altho the control is positive under ordinary conditions, the device is operated only semi-occasionally with a result that it becomes inoperative from corrosion and other causes. This condition is particularly dangerous in locomotive service.

It is one of the main objects of the invention to overcome this overspeeding in a practical and simple manner.

The foregoing, together with such other objects as may hereinafter appear, or are in cident to my invention, I obtain by means of a construction which I have illustrated in preferred form in the accompanying drawings, wherein:

Fig. 1 is a diagrammatic broken out side elevation of a locomotive equipped with my improvements Fig. 2 is an enlarged vertical section thru the control mechanism of my invention, and

Fig. 3 is a section taken on the line 3-3 of Fig. 2.

Referring now to Fig. 1, the reference numeral 7 denotes a rotary feed-water pump such as shown in the application of myself,- Serial No. 723,469, filed July 1, 1924, such pump taking feed-water from the tender tank by means of the pipe 8 and delivering feed water to the feed-water heater 9 by means of the delivery pipe 10. From the feed-water heater, the feed water is conduct-ed to the boiler check 11 by the pipe 12. The steam for operating the pump is delivered from the turret in the cab by the pipe 13 and the exhaust steam discharged from the pump is conducted to the feed-water heater by means of the pipe 14.

The control apparatus for preventing overspeeding of the pump is indicated at. A. in

Fig. 1. This cont-r01 device comprises the valve body or casing 15, suitably connected into the steam supply line. The flow of operatlng steam to the casing is controlled by the valve 16 and by the valve 17. At its lower end the valve 16 is provided with a piston 18 fitting within the cylindrical portion 19 of thecasing. The piston 18 is subjected to the delivery pressure of the pump 7 by virtue of the pipe 20 leading from the delivery pipe 10 to the bottom of the cylinder 19. The valve in the position shown in Fig. 2 is balanced. The spindle 21 of the valve is provided with a port 22. This port is controlled by the valve 17.

The operation is as follows:

The valve 17 is manually opened uncovering the port 22 and a limited quantity of steam flows to the pump 7, which, under the steam thus supplied, cannot race or overspeed. As the discharge pressure, or delivery pressure, of the pump builds up, this pressure becomes effective on the lower face of the piston 18 which causes the valve 16 to open widely permitting full steam to flow into the pump. The valve stays in this position as long as the delivery, or discharge pressure of the pump remains at normal value. If for any reason this delivery pressure should drop, when, of course, the pump would have a tendency to race, the valve 16 will return to its seat.

It will be appreciated that the manual oper ation of the valve 17 to shut down the pump necessarily involves moving the valve 16. Hence, there is no liability of the valve. 16 sticking through corrosion or accumulation of foreign matter.

Another advantage is that should there be condensate in the line, it is impossible for the engineer to deliver more than a limited quantity of steam to the turbine of the pump.

Another of the advantages of the invention is that the tendency of the valve controlling the pump steam supply to open or close is governed by the difference of pressure as between the pump steam inlet pressure and pump delivery pressure whereby an apparatus is provided in which very sensitive response is secured.

WVhile I have described my invention as applied to the feed-water system of a locomotive, it will be obvious that the invention has a. variety of applications.

In a locomotive feed-water system, it may prove desirable to supply a relief valve 23 in the delivery line to prevent overspeeding if the boiler check is screwed down or some other valve is closed in the discharge line.

I claim:

1. The combination with a fluid driven pump, of a control means therefor including a casing in the fluid line, a controlling valve member having a port, a connection from the delivery side of the pump for subjecting said valve to the delivery pressure, and a manually operated valve controlling the port. 2. The combination with a fluid driven pump, of a control means therefor including a casing in the fluid line, a controlling valve member, means whereby said valve is directly subject to delivery pressure from the pump, a by-pass, and a valve controlling the lay-pass. 3. The combination with a fluid driven pump, of a control means therefor including a pair of members cooperating to control the fluid supply, one of said members being hand operated in opening and closing and the other being subject to the delivery pressure of the pump in opening and being normally, manually closed.

4:. In combination, a fluid driven pump, a

source of supply of driving fluid, a valve chamber, a valve member tending to close under the influence of the pressure of the fluid leaving the valve and to open under the influence of the pump delivery pressure, and means for subjecting said valve to the pump delivery pressure.

5. In combination, a fluid driven pump, a source of supply of driving fluid, a valve chamber, a valve member tending to close under the influence of the pressure of the fluid leaving the valve and to open under the influence of the pump delivery pressure, means for subjecting said valve to the pump delivery pressure, and manually operated means whereby said valve member may be closed.

6. In combination, a fluid driven pump, a source of supply of driving fluid, a valve chamber, a valve member tending to close under the influence of the pressure of the fluid leaving the valve and to open under the influence of the pump delivery pressure, means for subjecting said valve to the pump delivery pressure, a by-pass for passing driving fluid to the pump, and manually operated means whereby said valve member may be closed and said by-pass controlled.

7. In combination, a fluid driven pump, a source of supply of driving fluid, a valve chamber, a valve member tending to close under the influence of the pressure of the fluid leaving the valve and to open under the influence of the pump delivery pressure, and a by-pass for passing driving fluid to the pump when said valve member is closed.

8. In combination, afluiddriven pump,

a source of supply of driving fluid, a valve chamber having a driving fluid inlet and outlet, a disc valve member for controlling the flow of the driving fluid, and means for subjecting said disc valve member to the pump delivery pressure whereby to open said valve member, said valve member tending to close under the influence of the pressure in the out let side of said valve chamber.

9. In combination, a fluid driven pump, a source of supply of driving fluid, a valve chamber, a valve member tending to close under the influenceof the pressure of the fluid leaving the valve, means for subjecting the valve member to the delivery pressure of the pump for opening the same, and an adjust able abutment functioning as a means for closing the valve and also as a means for limiting the extent of opening of the valve.

10. In combination, a fluid driven pump, a source of supply of driving fluid, a valve chamber, a valve member tending to close under the influence of the pressure of the fluid leaving the valve, means for subjecting the valve member to the delivery pressure of the pump for opening the same, and manual means for controlling the delivery of the pump by controlling the opening of the aforesaid valve member.

11. In combination, a fluid driven pump; a source of supply of driving fluid; and means for controlling the operation of the pump including a valve having aby-pass, a manually operable valve for said by-pass, which, when opened, admits driving fluid to the pump through the medium of the by-pass, and means for subjecting the first mentioned valve'to the delivery pressure of the pump whereby to open said valve, said valve being closed by the pressure of the discharge driving fluid when the delivery pressure of the pump drops abnormally and said manually operable valve also serving as an abutment for the first mentioned valve whereby the can tent of opening thereof governs the delivery of the pump.

12. In combination, a fluid driven pump; a source of supply of driving fluid; and means for controlling the operation of the pump, including manually operated means for slow speed and low pressure control of the pump and automatic means for high speed and high pressure control of the pump, said automatic means taking effect when a predetermined pressure is built up under control of the hand operated means, and being adapted to return the pump to control by the manually operated means in the event that the delivery pressure of the pump drops belowrthe aforesaid predetermined pressure, said manually operated means operating to determine the value of the high speed and pressure.

13. The combination in a locomotive of a feed water pump, a boiler check, a delivery line from thepump to the boiler check, a relief valve in said line, a source of supply of driving fluid for sald pump, valve means for controlling the pump adapted to cut off the driving fluid from the pump under the influence of the pressure of the fluid leaving said valve means and to pass fluid to the pump under the influence of the pump delivery pressure, and means for subjecting said valve means to the pump delivery pressure.

14. In combination, a pump and fluid driven engine therefor, a source of driving fluid supply, a valve chamber, a valve tending to close under the influence of pressure at the inlet side of the driving engine, and means whereby the valve tends to open under the influence of pump delivery pressure.

15. In combination, a pump and fluid driven engine therefor, a source of driving fluid supply, a valve chamber, and a valve controlled as to its tendency to open or close by the differential pressure between pump discharge and the pressure at the inlet side of the driving engine.

16. The combination in a locomotive of a feed Water pump, a boiler check, a delivery line from the pump to the boiler check, a source of supply of driving steam for said pump, valve means for controlling the pump, and means for opening and closing said valve means by the differential pressure between pump discharge pressure and pump inlet steam pressure.

In testimony whereof, I have hereunto signed my name.

CHRISTOPHER A. SCHELLENS. 

